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 Risorse Ambientali |  Geotermia e termalismo | GEOTHERMAL ENERGY AND THERMALISM
The complicated geological history of Val di Cecina was enriched in the last 3-4 million years, of an additional page: the intrusion of a magmatic body at low depth (6/7 km of depth), boasting various branches, which characterises the territory south of River Cecina, covering an area of about 400 square km. The result is the so called “Regione Boracifera” (Boraciferous Region), distinguished by an extensive and powerful hydrothermal system characterised on the surface by suggestive manifestations: soffioni, great lakes, fumaroles, hot springs (putizze) and thermal springs.
In addition to the well known soffioni of Lardarello, renowned for their historical importance linked to the industrial exploitation of the resource, various places are visible and easy to reach, where it is possible to observe various manifestations: the great lakes (lagoni) and fumaroles of Sasso, in the suggestive “Valle del Diavolo”, the Red Lakes (Lagoni Rossi), the Biancane of Monterotondo, who took their name due to the rocks dried by geothermal fluids. A series of interesting places follows, in which it is possible to admire the following heritage: the Sulphur mine of Libbiano and the Sulphur mine of Micciano can be visited through non marked paths. The excavations of the Thermal baths of Bagnone which are very interesting, also in historical terms, must be seen: they consist of an extensive Etrurian-Roman thermal complex which witnesses the exploitation of geothermal resources since ancient times. Still visible, along torrent Possera, there are also the Thermal baths of Morba, identified as Aquas Volaternas in the Tabula Peutingeriana (famous military Roman map dated back to the 3rd century A.C), also in operation during the Middle ages and Renaissance, which saw among their guests Lorenzo de’ Medici.
A history of 25 centuries
The mud and the water rich in boron and sulphur have always been beneficial to treat skin illnesses. Already since the Etrurians and Romans, but especially during the Middle ages, in addition to the use of hot waters for thermal purposes, minerals were extracted which were associated to geothermal manifestations such as sulphur, alum, green or martial vitriol (hydrated ferrous sulphate), blue vitriol (copper sulphate), boric acid (known as Nitre of Volterra). These products were used for pharmaceutical purposes such as oils, for a series of crafts activities such as wool carding and colouring, leather tanning, and for the glass and ceramic industry and welding of jewelleries. The historical archives of Val di Cecina, those of Volterra and Castelnuovo V. C, included very interesting data on the exploitation of mineral resources.
In 1777 U. F. Hoefer found boric acid in geothermal waters. In 1827 F. De Larderel created a suction system of natural vapour found in the sub-soil (“underground lake”) which was used to evaporate the waters rich in boric acid. This marked the beginning of the industrial use of boric waters and the exploitation of endogenous heat for the production of electric energy. In 1904, Price Ginori-Conti, by using a steam engine combined to a small dynamo, was able to transform the steam power into electric energy; in 1930, the first geothermal plant of Larderello was built.
For who wishes to learn in-depth the history of this area and its industrial evolution linked to geothermal energy, please visit the Museum of Geothermal energy of Larderello.
While the production of boric acid ended a few years ago, the production of electric energy still continues to grow. During the last few years, new power plants have been built and the existing ones have been renewed, thus reaching an installed power of about 207 Mw.
Heat transfer plants that feed throughout the area remote heating systems, greenhouses, industrial plants and aquaculture plants have positively affected in energy terms, the life of who lives in this geothermal area. |
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 Geotermia e termalismo | |
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